<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>无标题文档</title>
<script type="text/javascript">

window.onload = function(){
	var btn = document.getElementById('btn');
	var pic = document.getElementById('pic');

	btn.onclick = function(){
		// 改掉图片的src属性
		pic.setAttribute('src','gaoyuanyuan.jpg');
	}

}

</script>
</head>

<body>

<input type="button" value="变！！！！！" id="btn" />
<br /><br />
<img src="dog.jpg" id="pic" />

</body>
</html>
